The invention relates to a method of packaging living organisms so that they can be stored for a long period of time in adverse environmental conditions yet while still remaining viable, and to a package produced thereby. Conventionally, it is difficult, if not impossible, to package living organisms, such as nitrogen fixing bacteria and the like, so that they can be handled normally, shipped, and stored, without resulting in death of the organisms. Microorganisms are extremely vulnerable to death from starvation, heat, cold, airborne chemicals, and other environmental factors, and packaging them in conventional containers substantially reduces the number of viable organisms that can be delivered for a given end use.
Containers to adequately protect microorganisms in their vegetative state normally are too expensive to achieve widespread use, are generally nondisposable, and often require special handling--yet still are effective only for relatively short periods of time. Also, sterile conditions often are required during packaging, or other special conditions.
According to the present invention, a packaging method, and the package so produced, are provided that essentially overcome all of the above-mentioned problems with respect to microorganism packaging. According to the present invention, a large number of viable microorganisms can be delivered in a form eminently suited for a desired end use in an inexpensive and simple manner. According to the present invention, no special handling is necessary, although a large number of viable microorganisms can still be delivered even after long storage periods.
According to the present invention, the microorganisms are induced to assume a nonvegetative state in which the organisms are dormant. In such a state, whether it be a cyst or spore, the microorganisms are much better able to resist temperature changes and chemicals, and because they are dormant, do not require food. Also, since competing organisms will also become dormant, there is no need to ensure sterility of the microorganism carrier.
According to the method of the present invention, packaging of living organisms is practiced consisting essentially of the steps of mixing the living organisms with a carrier; disposing the organism-carrier mixture in a package; providing a gaseous atmosphere in the package effective to induce and maintain substantial nonvegetative state formation of the organisms; and sealing the package to prevent contamination of the atmosphere therein. The atmosphere providing step may be accomplished by providing an atmosphere selected from the group consisting essentially of nitrogen, helium and argon gases, although other gases may be effective to induce and maintain substantial nonvegetative state formation depending upon the particular microorganism. Peat has been found to be an effective carrier, although other carriers may also be effective depending upon the particular organism and the end use to which it should be put. In particular, the carrier may comprise a substantially granular material suitable for maintaining the organisms in a viable condition over a long period of time and for effecting utilization of the organisms for end purposes.
The invention is not limited to the particular type of microorganism packaged, and any microorganism capable of nonvegetative state formation as a result of exposure to a given gaseous atmosphere is considered within the scope of the invention. However, the invention is especially suitable for agricultural uses. For instance, with the decreasing availability of natural gas and petroleum products, other sources of agricultural nitrogen supplements are becoming feasible. For instance, nitrogen fixing bacteria, such as Azotobacter chroococcum, have been found effective in greatly increasing nitrogen levels when applied to plant roots, seeds, or the like. Packaging of the microorganisms with a carrier, such as peat, which facilitates the application of the microorganisms over a large volume of seed, roots, or the like, while providing an environment in which the microorganisms can live, can be extremely effective in providing marketability of such microorganisms.
Similarly, according to the present invention, a package of living organisms is provided consisting essentially of the living organisms mixed with a carrier; gaseous atmosphere means for inducing and maintaining substantial nonvegetative state formation with the organisms; and a sealed envelope surrounding the carrier, organisms, and atmosphere for preventing contamination of the atmosphere. The sealed envelope may be opaque, or an opaque label may be employed.
It is the primary object of the present invention to provide a method of packaging, and a resultant package, which preserves microorganism viability in an inexpensive manner even over long periods of time despite adverse environmental conditions. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.